The present invention relates to a cleaning apparatus for cleaning a substrate, such as a liquid crystal glass substrate, semiconductor wafer, a magnetic disk or the like, required to be cleaned.
Hitherto, subjects required to be cleaned, such as liquid crystal glass substrates, semiconductor wafer or magnetic disks, have been cleaned such that a plurality of the substrates are stood erect in a processing chamber, and then cleaning fluid is poured into the processing chamber, followed by operating an oscillator disposed in the bottom portion of the processing chamber to radiate high-frequency acoustic waves to the cleaning fluid so that the plural substrates in the processing chamber are cleaned at a stretch.
However, the trend of enlargement of the liquid crystal glass substrate and that of the diameter of semiconductor wafer arise a difficulty for the above-mentioned method to uniformly clean the overall surface of the substrate required to be cleaned. Thus, there arises a problem in that the cleaning process suffers from irregular results. Since thin film transistors, to be formed on the liquid crystal glass substrate, and devices, to be formed on the semiconductor wafer, have been fined and mounted densely, the reverse side of the substrate must precisely be cleaned as well as the right side (the side on which the devices and so forth will be formed) of the substrate.
Therefore, substrates (for example, silicon wafer) required to be cleaned are transferred by a single transfer method to clean the substrate on the transfer passage by rinse shower, chemical scrub, pure water scrub, a high-frequency cleaning nozzle, pure water shower and spin drying.
However, since the scrub cleaning process is performed by mechanically bringing a pair of sponge-type rolls into contact with the two sides of the silicon wafer, there arises a problem in that the two sides of the wafer are damaged or contamination particles are allowed to again adhere to the two sides and thus the two sides are again contaminated.